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Scagliola (from the Italian ''scaglia'', meaning "chips"), is a technique for producing stucco columns, sculptures, and other architectural elements that resemble inlays in marble and semi-precious stones. The Scagliola technique came into fashion in 17th-century Tuscany as an effective substitute for costly marble inlays, the ''pietra dura'' works created for the Medici family in Florence. Scagliola is a composite substance made from selenite, glue and natural pigments, imitating marble and other hard stones. The material may be veined with colors and applied to a core, or desired pattern may be carved into a previously prepared scagliola matrix. The pattern’s indentations are then filled with the colored, plaster-like scagliola composite, and then polished with flax oil for brightness, and wax for protection. The combination of materials and technique provides a complex texture, and richness of color not available in natural veined marbles. A comparable material is terrazzo. "Marmorino" is a synonym, but scagliola and terrazzo should not be confused with plaster of Paris, which is one ingredient. == Method == Batches of pigmented plaster (ground alabaster or gypsum) modified with animal glue are applied to molds, armatures and pre-plastered wall planes in a manner that accurately mimics natural stone, breccia and marble. In one technique, veining is created by drawing strands of raw silk saturated in pigment through the plaster mix. Another technique involves trowelling on several layers of translucent renders and randomly cutting back to a previous layer to achieve colour differential similar to jasper. When dry, the damp surface was pumiced smooth, then buffed with a linen cloth impregnated with Tripoli (a siliceous rottenstone) and charcoal; finally it was buffed with oiled felt; beeswax was sometimes used for this purpose. Because the colours are integral to the plaster, the pattern is more resistant to scratching than with other techniques, such as painting on wood. There are two scagliola techniques: in traditional ''Bavarian'' scagliola coloured batches of plaster of Paris are worked to a stiff, dough-like consistency. The plaster is modified with the addition of animal glues such as isinglass or hide glue. ''Marezzo scagliola'' or ''American scagliola'' is worked with the pigmented batches of plaster in a liquid state and relies mainly on the use of ''Keene's cement'', a unique gypsum plaster product in which plaster of Paris was steeped in alum or borate, then burned in a kiln and ground to a fine powder; invented around 1840, it sets to an exceptionally hard state.〔Theodore H. M. Prudon, "Simulating Stone, 1860–1940: Artificial Marble, Artificial Stone, and Cast Stone". '' Association for Preservation Technology International Bulletin'' 21.3/4 (1989), pp. 79–91.〕 It is typically used without the addition of animal glues. ''Marezzo scagliola'' is often called ''American scagliola'' because of its widespread use in the United States in the late nineteenth and early twentieth century. Slabs of ''Marezzo scagliola'' may be used as table tops. When set, scagliola is hard enough to be turned on a lathe to form vases, balusters and finials. The scagliola in the allen county courthouse (Seen on the right) was added to and repaired over three years by company Hayles and Howe which started work there in 1997. The ceo, David Hayles,(Who has probably made and restored more scagliola then any other person alive,) is the author of the definitive book on scagliola. It includes its history and a detailed method for making traditional and marezzo scagliola. Learn more about David Hayles and scagliola at themagicofscagliola.com 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Scagliola」の詳細全文を読む スポンサード リンク
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